Upper Darby police say 27-year-old Delaina Garling went to the Family Dollar Store on Monday, a place she'd been banned from for an incident involving alleged theft and fire alarm being pulled.
Police Superintendent Michael Chitwood says surveillance video shows Garling with her two young stepchildren.
In the video, she is told to leave the store, but as she departs, she allegedly pepper sprays the manager.
The manger reacts by going after Garling, who is wrestled down.
40 seconds into the incident, the 8-year-old boy hands his 7-year-old sister the can of pepper spray.
"The stepmother is screaming to the little girl 'you know what to do, baby. Spray her,'" Chitwood said.
A clerk takes away the spray. Chitwood says the girl never used the spray.
Garling, who has no adult record, is arrested.
"I feel bad for these kids. What kind of shot do they have when they are getting parental guidance like this?"" Chitwood said.
Police say they found marijuana on her and a controlled substance used for anxiety and seizure disorders.
Family Dollar customers are shaking their heads about the impact on the little children.
"This is crazy that the mother would ask the child to spray someone else," Lyne Johnson of Overbrook said.
"In the video, it looks as though the little girl was doing what the mother was telling her to do. God forbid if it was gun. What would she say? Shoot her? I mean, that's the sad commentary," Chitwood said.
Garling is charged with simple assault and other counts.
She remains in jail in lieu of a $35,000 bail with a 10% option.
Action News is told the 7-year-old and 8-year-old are now with their father.